ANNETTE F. BRAUN 
161 
chitinizod ridj>e extending along the underside of the second anal 
vein of the fore wing (or rarely along the base of the anal furrow), 
or catches into a series of siniiliar spines on the underside of the 
fore wing and functions to hold the wings together in flight, in 
place of either frenuluin or functional juguni, is preserved in 
better condition than elsewhere in the Lepidoptera. Its homol- 
ogy with similar functional structures in Trichoptera can 
scarcely be (piestioned. That the presence in males of a single- 
sjiined frenulum is not inconsistent with otherwise primitive 
structure is shown liy the fact that in some Trichoptera, both 
true frenulum spines and the series of hooked siiinesare presents 
As noted before, a similar condition is occasionally found in 
Nepticula, where both functional curved spines and single-spined 
frenulum occur together. 
Such considerations suggest the possibility that the Xepticu- 
lidae may have been derived from ancestry of coordinate rank 
with the Micropterygidae, rather than that they are descended 
from that group itself. 
, The \enation affords but little clue to the origin of the group. 
The tendency toward crowding together and anastomosis of the 
main tracheal branches is unique in the Lepidoptera, but it is 
perhaps significant that a similar tendency is seen in some of the 
small Trichoptera. The absence of true cross veins (the humeral 
cross vein alone is occasionally present) might be regarded as a 
primitive character; on the other hand it may be directly due to 
the anastomosis of the main veins. 
Key to the Genera 
(European genera are included in brackets for convenience) 
A. Rs (vein seven) of fore wing present. 
B. Media of fore wing with three branches (veins four, five and si.x present). 
[Scoliaula] 
BB. Media of fore wing with one or two branches. 
C. Media of fore wing with two liranches (vein four absent). 
D. Media of hind wing two-branched (veins five and six present). 
4. Glaucolepis 
DD. Media of hind wing single-branched 3. Obrussa 
^Cf. Kellogg, \. L., The Affinities of the Lejiidopterous Wing;” Ainer. 
Nat., xxix, pp. 709 to 719, (189o). 
TKANS. A.M. ENT. SOC., .XLIII. 
